Lennox Hearth Products Montebello LSM40MN-2 Installation Instructions Manual page 12

B. Attach vent components to appliance
- Secure Vent SV8 direct vent system compo-
nents are unitized concentric pipe components
featuring positive twist lock connections (see
Figure 15).
All of the appliances covered in this document
are fitted with collars having locking inclined
channels. The dimpled end of the vent com-
ponents fit over the appliance collar to create
the positive twist lock connection.
First Vent
Component
Align the dimple (four places)
with the opening of the locking
incline channel on appliance
collar. Twist vent component
clockwise to engage and seal.
Dimple
Locking
Incline Channel
Appliance collar
Vent / Appliance Collar
Connection
Figure 15
Arrow
Align the dimple (four places) of the
upper vent section with the opening of
the locking incline channel on the
lower vent section. Twist vent
component clockwise to engage and
seal until arrow and dimple align.
Dimple
Locking
Incline Channel
Connected
Vent Sections
Vent / Vent Section
Arrow
Connection
Figure 16
To attach a vent component to the appliance
collar, align the dimpled end over the collar,
adjusting the radial alignment until the four
locking dimples are aligned with the inlet of
the four inclined channels on the collar (refer
to Figure 15). Push the vent component against
the collar until it fully engages, then twist the
component clockwise, running the dimples
down and along the incline channels until they
seat at the end of the channels. The unitized
design of the Secure Vent components will
engage and seal both the inner and outer pipe
without the need for sealant or screws. If desired
a #6 x 1/2" screw may be used at the joint, but
it is not required as the pipe will securely lock
when twisted.
12
C. Attach vent components to each other
- Other vent sections may be added to the
previously installed section in accordance with
the requirements of the vertical vent figures
and tables. To add another vent component
to a length of vent run, align the dimpled end
over the inclined channel end of the previously
installed section, adjusting the radial alignment
until the four locking dimples are aligned with
the inlets of the four incline channels of the
previous section.
Push the vent component against the previous
section until it fully engages, then twist the
component clockwise running the dimples down
and along the incline channels until they seat at
the end of the channels. This seating position
is indicated by the alignment of the arrow and
dimple as shown in Figure 16.
D. Install firestop/spacer at ceiling - When
using Secure Vent, use SV8BF firestop/spacer
at ceiling joists. If there is living space above
the ceiling level, the firestop/spacer must be
installed on the bottom side of the ceiling. If attic
space is above the ceiling, the firestop/spacer
must be installed on the top side of the joist.
Route the vent sections through the framed
opening and secure the firestop/spacer with
8d nails or other appropriate fasteners at each
corner. Remember to maintain 1" (25 mm)
clearance to combustibles, framing members,
and attic or ceiling insulation when running
vertical chimney sections. Attic insulation
shield (H908) may be used to obtain the
required clearances indicated here. See
installation accessories on Pages 24 and 25.
The gap between the vent pipe and a vertical
Arrow
firestop can be sealed with non-combustible
caulking.
E. Support the vertical vent run sections -
Note - Proper venting support is very important.
The weight of the vent must not be supported
by the fireplace in any degree.
Support the vertical portion of the venting
system every 8 feet (2.4 m) above the fireplace
vent outlet. One method of support is by utiliz-
ing field provided support straps (conventional
plumber's tape). Secure the plumber's tape to
the framing members with nails or screws. Strap
the tape around the vent, securing the ends of
the tape to the framing. If desired, sheet metal
screws #6 x 1/2" length may be used to secure
the support straps to the vent pipe.
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
F. Change vent direction to horizontal/inclined
run - At transition from or to a horizontal/inclined
run, install the SV8 E45 and SV8 E90 elbows in
the same manner as the straight vent sections.
The elbows feature a twist section to allow them
to be routed about the center axis of their initial
collar section to align with the required direc-
tion of the next vent run element. Twist elbow
sections in a clockwise direction only so as
to avoid the possibility of unlocking any of
the previously connected vent sections. See
Figure 17.
6"
(153 mm)
Swivel Joint
Swivel Joint
(360° swivel)
(360° swivel)
SV8E45
SV8E90
(45 Elbow)
(90 Elbow)
Figure 17
G. Continue installation of horizontal/inclined
sections - Continue with the installation of the
straight vent sections in horizontal/inclined run
as described in Step C. Install support straps
every 3' (914 mm) along horizontal/inclined
vent runs using conventional plumber's tape. It
is very important that the horizontal/inclined
run be maintained in a straight (no dips)
and recommend to be in a slightly elevated
plane, in a direction away from the fireplace
1/4" per foot (20 mm per meter) which is ideal,
through rise per foot run ratios that are smaller
are acceptable all the way down to at or near
level. Use a carpenter's level to measure from a
constant surface and adjust the support straps
as necessary.
It is important to maintain the required clear-
ances to combustibles: 1" (25 mm) at all sides
for all vertical runs; and " (76 mm) at the top,
1" (25 mm) at sides, and 1" (25 mm) at the
bottom for all horizontal/inclined runs.
H. Frame roof opening - Identify location for
vent at the roof. Cut and/or frame opening
per Roof Framing Chart and Figure 18 on
Page 13.
10"
(254 mm)